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Why is a C++ Vector called a Vector?
...Mathematical definition of a vector is a member of the set Sn, which is an ordered sequence of values in a specific set (S). This is what a C++ vector stores.
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How to change Rails 3 server default port in develoment?
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First - do not edit anything in your gem path! It will influence all projects, and you will have a lot problems later...
In your project edit script/rails this way:
#!/usr/bin/env ruby
# This command will automatically be run when you run "rails" with Rails 3 gems installed from the root...
What does the regular expression /_/g mean?
...egex matches the _ character.
The g means Global, and causes the replace call to replace all matches, not just the first one.
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Does pandas iterrows have performance issues?
...rows should only be used in very, very specific cases. This is the general order of precedence for performance of various operations:
1) vectorization
2) using a custom cython routine
3) apply
a) reductions that can be performed in cython
b) iteration in python space
4) itertuples
5) iterro...
What is 'Context' on Android?
...ation class keeps tracks of a list of Activities that it’s monitoring in order to do its work. This list is used to coordinate all of the activities and make sure everything runs smoothly in managing the flow of activities.
There are some operations that I haven’t fully looked into which coordi...
Physical vs. logical / soft delete of database record?
...he isDeleted column, I suggest the usage of two different tables: one with orders and another with deleted orders. In that case, you will have to maintain both the table, but in reality, it is very easy to maintain. When you write UPDATE statement to the isDeleted column, write INSERT INTO another t...
Use logging print the output of pprint
...at much overhead that it's worth the trouble of adding the conditionals to all the DEBUG log statements?
– undefinedvariable
Sep 29 '15 at 13:04
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elasticsearch v.s. MongoDB for filtering application [closed]
...rms of which fields are used for the filtering at any moment", it could be orders of magnitude faster, especially as the datasets become larger. The difference lies in the underlying query implementations:
Elastic/Lucene use the Vector Space Model and inverted indexes for Information Retrieval, wh...
Global variables in Java
...ggest your rename your class from Global to something else (TestClass?) in order not to give people the impression that there is such a thing as a Global Java keyword. Better safe than sorry :)
– Nicolas Rinaudo
Jul 25 '13 at 13:36
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Swift: #warning equivalent
...builds clean in production, but I get a warning in development that essentially reminds me I'm in dev mode - using different URLs, timeouts, other settings etc. Arie's suggestion above lets me do this, your technique just flags everything. That said, this technique has its use for sure so I up voted...